This invention relates to an electrical socket to be connected to an electric connection object such as an IC chip.
For example, Japanese Patent (JP-B) No. 3103760 discloses an IC socket having an IC pressing mechanism for pressing an IC to achieve stable contact. The IC pressing mechanism has a structure such that a rotary latch lever is pressed by an edge portion of an actuator (cover). However, since the edge portion and the rotary latch lever move in frictional contact with each other, abrasion powder is produced. The abrasion powder not only becomes a factor increasing an operating force but also may possibly cause a contact failure. In addition, it is difficult to adapt the IC socket to an IC chip having a large number of contacts and to provide the IC socket at a low cost.
Japanese Patent (JP-B) No. 3044460 discloses a socket for testing a semiconductor package, which is capable of preventing a contact failure by holding the semiconductor package with its upper side pressed downward. The socket comprises a plurality of metal contacts of a normal pressing type (the socket has a sheet-connector structure). However, a contacting force of each contact is large. Therefore, if the number of the contacts is large, a spring of a pusher must have an increased pressing force and an operating force inevitably becomes very large.
Japanese Unexamined Patent Application Publication (JP-A) No. H7-14652 discloses an IC package socket capable of mounting and removing an IC package in an unloaded condition. The IC package socket has a structure in which a movable cam is rotated by depressing a cover to displace contacting portions of contacts against an elastic force of a spring portion. However, each contact itself must have a complicated structure and, therefore, the socket can not easily be formed. In addition, each contact is easily deformed. Therefore, adjacent ones of the contacts may be contacted with each other to be short-circuited or the contacts may be nonuniform in contacting condition. Thus, a stable contacting state can not be achieved.